It is common practice to collect light and transmit light or electromagnetic energy from one location to another location in the form of rays or beams. In the past, light, which has been radiated in many directions, has been collected, and then relayed, focused or scanned by mirrors, lenses, and/or prisms. Optical light beams diverge and broaden, but they can be refocused by the use of lenses and mirrors. When using lenses, a typical condenser system (e.g., lens to collect light) projects the source of light onto an image plane. Since the light source is imaged, the light source should be generally uniform to enhance uniformity at the image plane being illuminated. However, there are several drawback and disadvantages to such imaging systems. For example, the collection angle in condenser systems is generally low compared to other systems. Also, the condenser systems generally have a plurality of optical elements, and as such, increases the complexity of mechanically mounting each component of the system, and can increase the overall cost of the system. Furthermore, the light beam can be easily obstructed or scattered by various objects.
Another conventional system is guided-wave optical devices. Conventional guided-wave optical devices transmit light through dielectric conduits, which can provide long distance light transmission without the need or use of relay lenses. Generally, a guided-wave optical device is a light conduit that is configured as either a slab, strip, or cylinder of dielectric material, and generally having a rectangular vertical cross sectional shape along its respective longitudinal axis. These guided-wave optic devices utilize internal reflections to integrate and transport light to an image plane. Light reflects off the interface between the dielectric material and outside material (e.g., a material with an index of refraction less than the dielectric material, such as glass with an additive, or air) interface.
In use, however, light exiting these guided-wave optical devices are not generally focused, and the level of irradiance of the image plane object can rapidly decrease as the distance between light source and the image plane increases. This can be due to a number of factors, including light being lost or leaking out of the guided-wave optical device due to refraction because of a lower than desired collection angle. Materials are generally softer and more difficult to machine. Furthermore, such materials can be more expensive and can be a more hazy material.
As can be seen, currently available optical devices and systems have a number of shortcomings that can greatly reduce the amount of light and/or focus of the light being transmitted from the light source to the image plane. Moreover, light being emitted from conventional devices and systems is not always uniform and any source imperfections are transmitted through the device and system.